Combustion-control device



. Aug. 17, 1926.

G. s. cARRl'cK l coMBUsTIoN CONTROL DEVICE Filed Nov. 2.o, 1922 .lzvy 6er@ [6% 069712131?? 77W Patented Alig. 17, 1926..,

GERALD S. CARRICK,'OF CHICAGO, ILLINOIS.

coMBUsrIoN-coN'rnor. DEVICE.

Application led November 20, 1922. Serial No. 602,312.

This invention relates to improvements `in combustion control devices and more especially to such a device adapted for controlling the damper, draft, blower engine,

stoker or other boiler mechanism Ifor the` purpose of maintaining a more or less constant pressure or boiler output.

For the purpose of illustration in this. application, I have shown my improved device as operated by the steam press/ure from a boiler, and as controlling the 1 damper of the boiler. Itis obvious, however, that, without detracting from the spirit of this invention, the device may be arranged to control any other boiler mechanism such as the draft, blower engine, stoker engine or the like; and also instead of. being operated by pressure from the boiler it could, if desired, be operated by changes in pressure in' the fire-box, or other variants in connection with the boiler.

Among the ,features of my invention are the provision of means for varying the position of' he damper in an innite number of steps, from the 4Wide open position as one limit, to the entirely closed position as the other limit. Inother words, the damper will be balanced so that it will always take a definite position relative to the then existing pressure in the boiler. My improved mechanism will cause damper to change as the pressure changes.

It is to be noted that with my improved device, a heavy damper or other heavy mechanism can be delicatelyA controlled and adjusted in accordance with changes in the boiler pressure. To accomplish this I have provided independent power means for moving the damper; and my improved combustion control device controls such independent power means, thus indirectly controlling the damper. Such independent power means are eeetive to move heavy dampers, or other heavy mechanism, and overcome any resistance or friction thatA there might v. be in the adjustment of the damper or other device.

Other features and advantages of my invention will appear more fully as I proceed with my specification.

A form of device embodying the features of my invention is shown in the accompanyinor drawing, partlydiagrammatically.

lAs shown inthe drawing, pipe 1 is connected to. a steam boiler and leads to a reservoir 2, in which is placed a quantity the position of the,

of mercury 3. Another pipe 4 connects the bottom of the mercury tank 2 to a cylindrical reservoir 5 arranged above the mercury tank 2. Within the reservoir 5" is mounted afloat 6, having its upper end connected by means of a rod 7 to a yoke 8, the lower end of which is suitably connected toA a cable 10 extending downwardly and around afwheel 11. The cable 10, having passed around the wheel 11,

'extendsupwardly and is wound about a yielding downward pull.

drum 12 mountedon a horizontal rotatably supported shafty 13. On the end of the shaft 13 is` mounted a gear wheel 14 meshing with a Worm 15 mounted on theeiid of the rotatably supported shaft 16. The other end of the shaft 16 carries another worm 17 meshing with a gear 18 mounted on the end of a shaft'19. The shaft 19 also carries a` drum 20 about which is wound a .cable 21 extending upwardly and attached to the end of an arm 22 mounted on the end of a shaft 23 carrying a damper 24. Attached to the other end of the arm 22 is a counterweight 25 for the purpose of exerting. a Upward and downward movement of the arm 22 serves to move the' damper 24. `The damperjis shown substantially in its open position in the solid` lines and in its closed position in the broken lines. .A

The shaft 16 carriesy at its center a gear 30 meshing with a worm 31 mounted on the shaft of a reversible electric motor 33. 35

and 36 indicate thelead-in wires supplying current to the motor 33. These two wires lead to the contact blocks 35 and 36', respectively, onl a lever switch 37 pivoted at 38.

lever 37 carrying the contact blocks 35 and 36 is adapted to bring these blocks into contact .with the contact plates 40 and 41 to energize 'the circuit 44 leading to the motor. Downward movement of these blocks is adapted to'bring them in contact with the contact plates 47 and 48 in ordery to energize thev other circuit 49 leading to the motor. The motor is a reversible one and so wired that current delivered throughy the .circuit 44 will rotatey itin one directionandcurrent delivered through the circuit-..49 will rotate it in the opposite direction. "In this man- Upward movement of the end of the ner it is designed to give rotation to the shaft 16 in either direction depending upon the position of the switch arm l37. The

transmission yof movement through the ,l

- worm gears makes its impossible for power to be transmitted from the damper back to the motor.

The wheel 11 is mounted on an axle 70 which'is slidably mounted in two vertical ways or guides 71, thus permitting the wheel 11 to hang in the loop of the cable 10 and also permitting it to be moved upwardly or downwardly by means of said cable. The wheel 11 carries a bifurcated arm extending downwardly and attached to a member 73, which is provided with a' stud 74 located in the forked-end of the lever switch 37. Tt will be seen that upward and downward movement of the wheel l1 will therefore cause downward and upward movement of the end of the switch arm 37 carrying the contact blocks 35 and 36. The motor connections are so made that contact of the blocks 35 and 36 with the lower blocks 47 and 48 will cause rotation of the motor 33 in the proper direction to rotate the shaft 16 and drum 12 to unwind the cable 10 therefrom.

The operation of the device is as follows: In the drawing the damper 24 is 'shown in solid lines in substantially open position, and the float 6 is substantially at the bottom of its range of travel. It will be noted that the mercury 3 nearly fills the tank 2. The apparatus is so adjusted that when the parts are in this position, the boiler pressure will be substantially at its lowest point. With such low boiler pressure, it will be noted that the open damper 24 will increase the draft and re and consequently tend to 'f cause the boiler pressure to rise. As the downwardly boiler pressure rises theincreased pressure ywill be transmitted through the pipe 1 to the space in the mercury tank 2 above the mercury 3. This increased pressure will force the mercury 3 through the pipe 4 into the reservoir 5 and cause the float 6 to be raised. Raising of the oat 6 will operate throu h the cable 10 to lift the. wheel 1l; and t isl will move the lever 37, as explained above, to bring the contact blocks 35 and 36 in contact with the plates 47 and 48 to cause rotation of the motor 33 in the proper direction, to move the drum 12 to unwind the cable 10. This movement of the shaft 16 also operates on the drum 2O to wind up the cable 21. The winding up of the cable 21 operates on the arm 22 to cause the damper 24 to be moved towards its closed position. The unwinding ofV the cable 10 from the drum l2 lowers the member 73 to cause the Contact blocks 35" and 36 to move away from the contact plates 47 and 48 and stop rotation of the motor 33. It W11l be seen, therefore, that the damper 24 will be stopped in a certain position corresponding to the boiler pressure. Changes 1n the boiler pressure either upwardly or will thus cause movement of the wheel 11 to move the-switch 37 to cause rotation of the motor 33 to move the damper 24 in the corresponding direction. That is, increase of pressure will cause the damper 24 to move toward the closed position and decrease of pressure will cause it to rmove toward the open position. It is to be particularly noted, however, that as soon as the damper moves a little distance, movement of thedrum 12 will operate on the cable 10 through the wheel 11 to again open the switch 37 and stop movement of the motor. It will be seen, therefore, that the damper 24 is balanced so that it will always take a certain definite relative position with respect to the then existing boiler pressure and retain this position until the boiler pressure changes. With a device of this kind there will be no Hopping of the damper from'l a wide open position to a tightly closed position, or vice versa. The damper will be always-delicately adjusted or balanced in a certain position relative to the boiler pressure.

It is to benoted that the electric motor 33 furnishes the power to move the damper 24. There is, therefore, independent power means for moving the. damper. Such independent power means may be as strong as desired, to move la heavy or resisting damper.

`While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is my intention to claim all novelty inherent in my invention as broadly as possible in view of the prior art.

vVhat Iclaim as new and desire to secure by Letters Patent, is:

1. In a device of the character described, a control member adapted to be actuated by changes in pressure in a boiler and adapted to assume a set controlling position with lll) respect` to every different boiler Apressure by the independent electric power means to stop operation of said power means upon the combustion controlling member reaching a. position relative to the setting of the pressure actuated control member, said power controlling means comprising a member carrying a shea-ve with a rope passing thereover, one end of said rope being attached to the pressure actuated control member and the other to the independent power means.

2. In a device-of the character described,

'a control member adapted to be actuated by ated by the independent electric power means to stop operation of said power means upon the combustion controlling member reaching a position relative to the setting of the pressure actuated control member, said power controlling means comprising a member carrying a sheave with a rope passing thereover, one end o said rope being attached to the pressure actuated control member and the other to the independent power means.

3. In a device of the characterl described, a control member adapted to be actuated by `changes in pressure "in a boiler, a combustion controlling member, independent electric power means for actuating the combustion controlling member, means controlling said electric power means and adapted to be actuated both by the pressure. actuated control member and by said independent power means, said power controlling means comprising a pivoted lever carrying a sheave with a rope passing thereover, one end of said rope being attached to the pressure actuated control member and the other to the independent power means.

4. In a' device of the character described, a control member adapted to be actuated by changes in pressure in a boiler, a combustion controlling member, independent electric power means for actuating the combustion controlling member, means controlling said electric power means andadapted to be actuated both by the pressure actuated control member and by said independent power means, said power controlling means comprising a member carrying a sheave with a rope passing thereover, one end of said rope being attached to the pressure actuated control member and the other to the independent power means.

5. In a device of the character described, a reservoir containing iluid, means for changing the height of fluid in the reservoir in accordance 'with variations in pressure in a' boiler, a float in the Huid, a com bustion controlling member, independent reversible electric power means adapted to actuate the combustion controlling member,

and means for controlling the independent power means, said power controlling means including a pair of switches, and a member adapted to close one or the other of said switches, said last mentioned member carrying a sheave over, one end of said rope attached to said float and the other end attached to said independent power means.

Witness my hand lthis 24 day of October,

v GERALD S. CARRICK.`

having a rope` passing there- 

